class CarA():
    """汽车之家"""
    def __init__(self,manufcturer,model,year):
        """初始化操作，建立描述汽车的属性"""
        self.manufcturer = manufcturer
        self.model = model
        self.year = year
        self.odometer_reading=0

    def get_descriptive_name(self):
        """返回描述信息"""
        long_name = str(self.year)+ ' ' +self.manufcturer +' '+self.model
        return long_name
    
    def read_odometer(self):
        """行驶里程"""
        print("这是一辆新车，目前仪表显示行驶里程是" + str(self.odometer_reading)+" 千米")

    
"""
class Bmw(Car):
    '''这是一个子类Bmw，基类是Car'''
    def __init__(self, manufcturer, model, year):
        super().__init__(manufcturer, model, year)

my_Bmw = Bmw("宝马","535Li",'2017款')
print(my_Bmw.get_descriptive_name())
my_Bmw.read_odometer()

 """